1. Field of the Invention
This invention relates to phototherapy and more particularly pertains to a method and apparatus for exposing an observer to a precisely controlled display of light in order to achieve a therapeutic effect.
2. Description of the Prior Art
It has long been recognized that light can have profound psychological as well as physiological effects on the human organism. Although both ocular as well as non-ocular techniques have been employed in an attempt to achieve various such effects, ocular treatment appears to be most efficacious. Not only are the eyes highly specialized organs specifically adapted for sensing light, but a sizable portion of the brain is exclusively devoted to processing data generated by the retinas. Moreover, neurologists and anatomists have relatively recently demonstrated the existence of nerve pathways extending from the retinas that are separate and apart from the pathways linked to the sight center of the brain. These newly discovered interconnections link the eyes with neurological centers in the brain that influence and control many of the body's regulatory functions. Such regulatory centers typically exert their control via neurological or biochemical means.
An example of an organ whose regulatory function is responsive to light sensed by the eyes is the pineal gland which secretes the hormone melatonin. The hormone is released during periods of darkness while production is abruptly halted when the eyes perceive bright light. Melatonin is distributed throughout the body via the blood and cerebrospinal fluid and can effect the function of organs by which it is metabolized to thereby influence sleep cycles, feeding cycles, reproduction cycles and other biological rhythms. It has therefore been suggested that phototherapy may effectively be employed to correct a melatonin imbalance which may have resulted from, for example, shift work, jet lag or life in the polar regions, and thereby remedy the accompanying symptoms.
Other such relationships have been discovered, more are suspected and even more may, in fact, exist. Additionally, it has been found that some of the body's responses to light are acutely dependent upon specific characteristics of the light perceived by the eyes such as the light's wavelength, and intensity, and further, that particular responses can be elicited or enhanced by varying such characteristics according to certain sequences or patterns. Although instruments have been constructed and techniques devised to generally exploit this systemic sensitivity to light, many important factors had not been taken into consideration as required in order to take fuller advantage of the effect of light on the human organism. The present invention seeks to overcome some of these shortcomings.